1. Field
Embodiments of the disclosure herein relate to a refrigerator having an improved structure of fixing a heating pipe to an inner case.
2. Description of the Related Art
In general, a refrigerator refers to a device that keeps food fresh by including a body having an inner case and an outer case, a storage compartment formed by the inner case, and a cold air supplying unit for supplying cold air to the storage compartment.
The storage compartment may be maintained at a temperature in a predetermined range required to keep food fresh.
A front side of the storage compartment of the refrigerator may be disposed to be open, and the open front side of the storage compartment may be closed by a door so that the temperature of the storage compartment may be normally maintained.
An insulating material is foamed between the inner case and the outer case so as to prevent outflow of cold air in the storage compartment.
Since foaming of the insulating material is performed only at a predetermined temperature or higher, heat is generated while the insulating material is foamed. The body has a temperature approximately 20° C. higher than a room temperature in a state in which the insulating material is foamed between the inner case and the outer case.
After the insulating material is foamed between the inner case and the outer case, the temperature of the body is lowered to the room temperature so that the insulating material is solidified and the body thermally contracts.
Since the inner case is mainly formed of a plastic material and the outer case is mainly formed of a steel material and the plastic material has an approximately five times larger quantity of thermal contraction than that of the steel material, when the body thermally contracts, the inner case contracts greatly compared to the outer case and thus, while the temperature of the body is lowered to the room temperature, central parts of both sides of the body are deformed in a convex shape toward an outside of the body. In a state in which the temperature of the body is lowered to the room temperature, the insulating material is solidified in a state in which the central parts of both sides of the body are deformed in the convex shape toward the outside of the body.
When deformation occurs in the inner case and the outer case due to a difference in quantities of thermal contraction of the inner case and the outer case, deformation that occurs in the inner case and the outer case is reduced to a predetermined degree due to the insulating material that contacts the inner case and the outer case. By reducing the thickness of the insulating material foamed between the inner case and the outer case in order to increase an internal capacity of the body having the same exterior size, a quantity of deformation in which the central parts of both sides of the body are deformed in the convex shape toward the outside of the body, is increased by the reduced thickness of the insulating material. Even after the insulating material is foamed, when the refrigerator operates, the temperature of the body is lowered such that the quantity of thermal contraction of the inner case is further increased and a quantity of deformation of the shape is increased.
In addition, when the thickness of the insulating material is reduced, insulation performance may be lowered, and rigidity may be deteriorated such that deformation may occur in the body due to the weight of the body and a load of a material stored in the body.
In order to improve the insulation performance lowered due to the reduced thickness of the insulating material, a vacuum insulating material may be disposed between the inner case and the outer case together with the insulating material. The vacuum insulating material may be disposed between the inner case and the outer case together with the insulating material so as to supplement the lowered insulation performance, but deteriorated rigidity is not supplemented.